Induced valley splitting in monolayer MoS2 by an antiferromagnetic insulating CoO(111) substrate

Giant valley splitting in a MoTe2/MnSe2 van der Waals heterostructure with room-temperature ferromagnetism

“…This value is tens of times the splitting strength achieved in CrI 3 /WSe 2 , 20,21 and even exceeds the substantial value can be obtained in some typical heterostructures [see Table S1 in supplementary material for details]. [40][41][42][43] Owning to the large energy difference (i.e., valley splitting) between K and K' the use of optical excitation to obtain the spin-valley excitons on the two valleys can be carried out in a considerable spectral frequency range (…”

Valley polarization in monolayer CrX2 (X = S, Se) with magnetically doping and proximity coupling

“…Although valley polarization is indeed achieved by applying external magnetic field experimentally, the effect is rather modest as 1 T magnetic field can only lead to a splitting of 0.1-0.3 meV [30][31][32]. Compared with these two approaches, recently utilizing atom doping [20,[33][34][35][36][37] and magnetic semiconductor substrate [38][39][40][41][42][43][44] are shown to be more effective ways to achieve valley polarization. Nevertheless, as the interaction between host material and the substrate/doping may deform the valley feature, the magnetic substrate or transition metal must be selected carefully.…”

The Magnetic Proximity Effect Induced Large Valley Splitting in 2D InSe/FeI2 Heterostructures

“…On the other hand, the exchange valley splitting by MPE can generate fairly large tunable Zeeman splitting, which depends on the exchange interaction strength between the magnetic substrate and TMDCs, the interlayer separation and band alignment [ 16 ]. So far, there are intense studies of 2D materials to achieve the valley splitting via proximity exchange effect [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Theoretical work has predicted strong exchange effects and emergent phenomena in the systems integrating 2D materials with magnetic substances.…”

“…Theoretical work has predicted strong exchange effects and emergent phenomena in the systems integrating 2D materials with magnetic substances. For instance, many investigations have been performed for TMDCs on magnetic substrates such as EuO [ 17 ], EuS [ 18 ], MnO [ 20 , 21 ], CoO [ 19 ], Cr 2 O 3 [ 22 ], and CrI 3 [ 23 , 24 , 25 ], as well as other 2D systems: SnO/CrN [ 26 ], and 2H–VS 2 /Cr 2 C [ 27 ] to study their interfacial magnetic exchange effect. In addition, the in-plane strain, the vertical electric field and the layer separation can be used to further manipulate and modulate valley splitting in some of the above systems [ 16 , 21 ].…”